Saffron (Crocus sativus) ethanolic extract and its constituent, safranal, inhibits morphine-induced place preference in mice.

The effects of saffron ethanolic extract and its constituent, safranal, on the acquisition and expression of morphine-induced place preference (CPP) in male Swiss Webster mice (20-25 g) were investigated in the present study. An unbiased place conditioning method was applied for assessment of morphine reward properties. The saffron extract and safranal were administered intraperitoneally (i.p.) during (acquisition) or after induction (expression) of morphine CPP. In a pilot study, the extract and safranal were alone administered to the animals to assess if they have any reward properties. Subcutaneous (s.c.) of morphine (4 and 8 mg kg(-1)) and extract (50 mg kg(-1); i.p.) induced CPP. Extract (10, 50 and 100 mg kg(-1); i.p.) reduced the acquisition and expression of morphine CPP. The same results were obtained when safranal (1, 5 and 10 mg kg(-1), i.p.) was used. It may be concluded that both ethanolic saffron extract and safranal can inhibit the acquisition and expression of morphine-induced CPP in the mice.

The effects of lamotrigine on the acquisition and expression of morphine-induced place preference in mice.

The purpose of the present study is to determine the effects of the anticonvulsant drug, lamotrigine, on the acquisition and expression of morphine-induced place preference in mice. Lamotrigine prevents the release of glutamate from presynaptic neurons and inhibits action potential in postsynaptic area by inhibiting presynaptic sodium and calcium channels. Because of such properties, lamotrigine is used for reducing craving for and use of cocaine, alcohol and abused inhalant. So, to determine the effects of lamotrigine on opiates; specifically morphine, 180 male Swiss-Webster mice (20-35 g) were used in this study. Conditioned place preference, was assessed using a biased place conditioning paradigm. In a pilot study the effects of various doses of morphine (2.5, 5 and 10 mg kg(-1)), alone, or in combination with lamotrigine (1, 5 and 25 mg kg(-1)) on the place conditioning paradigm were examined. Animals were injected with the aforementioned doses of lamotrigine 60 min either prior to each morphine injections (acquisition) or prior to the start of the expression on the test day (expression). Administration of different doses of morphine (2.5, 5 and 10 mg kg(-1)) induced conditioned place preference whereas the administration of different doses of lamotrigine (1, 5 and 25 mg kg(-1)) failed to induce place preference. Acquisition and expression of morphine-induced CPP were reduced by lamotrigine at doses of 1, 5 and 25 mg kg(-1) and 5 and 25 mg kg(-1), respectively. Physiological mechanisms of action of lamotrigine and its potential therapeutic use in the treatment of drug-dependence are discussed.